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<p>&nbsp;<p>
<hr noshade size="5">
<h2><a name="PolyResultant"></a>
PolyResultant
</h2>

Computes the resultant of the two given polynomials.

<p><p>

<h3>
Syntax:
</h3>
<pre>r := PolyResultant (f, g);</pre>

<p>

<table>
<tr>
<td>polynomial</td>
<td><pre>  r  </pre></td>
<td></td>
</tr>
<tr>
<td>polynomial</td>
<td><pre>  f  </pre></td>
<td></td>
</tr>
<tr>
<td>polynomial</td>
<td><pre>  g  </pre></td>
<td></td>
</tr>
</table>

<p>


See also:&nbsp;&nbsp;<a href="kashref.html#PolyGcd">PolyGcd</a>

<p>

<h3>
Description:
</h3>
PolyResultant(f,g) = 0 if and only if f and g have a common factor
which has positive degree in x

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>

<pre>

kash> Zxy := PolyAlg(Zx);
Univariate Polynomial Ring in y over Univariate Polynomial Ring in x over Inte\
ger Ring

kash> f := Poly(Zxy,[1,2*x+4,x^2 +x,6*x]);
y^3 + (2*x + 4)*y^2 + (x^2 + x)*y + 6*x
kash> f_ := PolyDeriv(f);
3*y^2 + (4*x + 8)*y + x^2 + x
kash> PolyResultant(f,f_);
> -12*x^5 - 64*x^4 + 460*x^3 + 2828*x^2 + 1536*x

</pre>

<p>


<hr>

<p>
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